The soil nutrient profile, or soil fertility, weed control and sowing, are critically important when establishing improved pastures. They play an important role in determining whether or not a pasture becomes successfully established and influences the type of pasture that will best suit the production environment.
Some aspects of soil fertility can be manipulated easily and effectively eg phosphorus levels, while other aspects are more difficult to change and are better managed by working to the conditions eg salinity.
The only way to determine the soil nutrient profile is to undertake a soil test. This will reveal important attributes of soil fertility which may influence pasture species selection and fertiliser requirements.
Soil tests can be organised through local rural merchandise suppliers or rural consultant or you can take samples yourself and send these away for laboratory analysis. The way the soil is collected for analysis is important, with multiple samples required to make up a representative sample.
Soil tests vary in complexity depending on producer requirements. When considering establishing a pasture, the key aspects usually tested are pH, level of salt, available phosphorus, available sulphur and exchangeable cations (Ca, Mn, Na and K).
The results from soil testing must be considered within the context of the local farm environment and it is advisable to have the results interpreted by a local FertCare accredited agronomist or consultant.
A key outcome of soil analysis and interpretation is a fertiliser recommendation. Soil analysis prior to fertiliser application provides a guide to ensure the correct fertiliser application for the conditions, giving the pasture the best chance of becoming established and underpinning the investment in pasture improvement.
Fertilisers vary from relatively stable and low cost single super options containing phosphorus and sulphur, to more volatile compounds containing nitrogen and high analysis custom fertilisers. Other applications such as lime may also be recommended through soil analysis to correct fertility issues associated with pH.
By undertaking soil analysis prior to sowing producers can correct any soil fertility issues that may hinder pasture establishment. They can also implement an ongoing pasture management and fertiliser strategy to maintain pasture condition and maximise longevity without the need for regular soil testing.
Other issues that should be considered when developing a fertiliser program for improved pastures are:
- Choosing the right kind of fertiliser.
- Planning the timing of the application.
- Utilising additional production generated through the application.
- Ongoing monitoring of soil fertility.